Is L-Arginine good or bad for you? L arginine is safe to take. It is considered an amino acid and it is known to support healthy blood flow, improved athletic performance and recovery during critical illness.
L-Arginine is also known to be research wise for the development of T-cells and it plays a role in immune support response. It acts as a precursor to other amino acids and is vital in heightening the health of your immune system.
Improving Athletic Performance
There was a randomized study that was done on 56 soccer players, and they were given 2 grams of L-arginine daily. And this was for 45 days, and their sports performance significantly increased compared to the placebo group.

Is L-Arginine good or bad for you? Photo credit: iStock-natatravel
Another small study that was done in 9 men who drank a beverage that had 6 grams of L-arginine about 1 hour before an intense exercise. The results showed they were able to exercise longer compared to the placebo group.
There are also mixed studies that showed that L-arginine doesn’t impact exercise performance. So, the studies that are out there favor impacting and not impacting exercise so there are mixed.
Regulating Blood Pressure
Research studies have shown that taking L-arginine supplements can lower your systolic and diastolic blood pressure numbers. In 7 random studies it showed it lowered blood pressure levels with people that had high blood pressure.
Improving Erectile Dysfunction
Some other potential benefits that L-arginine supplements show are helping with erectile dysfunction while improving blood blow. There were 10 research studies in 2009 that showed that daily doses of 1.5 grams of L-arginine improved blood flow in erectile dysfunction compared to a placebo or no treatment.
Research studies also showed that taking L-arginine supplements during pregnancy helped prevent and treat preeclampsia. Preeclampsia is a condition that happens when you have high blood pressure and protein in the urine.
Some of the side effects to L-arginine are if you take large doses which would be 9 grams or more per day. And those side effects are bloating, abdominal pain, nausea, diarrhea, etc.
Some of medicines that L-arginine can interact with safely is:
- Blood Pressure Lowering medications.
- Diuretic medications
- Antidiabetic medications
- Blood thinning medications
- Erectile dysfunction medications
If you store it in a cool dry area that will help preserve the quality of the product as opposed to it being exposed to heat or moisture.
The Bottom Line is L-arginine is safe to take and studies have shown that it can help reduce your blood pressure levels. And it can help with improving blood flow and erectile dysfunction.
References
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